Healthcare environments, such as hospitals and clinics, typically include information systems (e.g., electronic medical record (EMR) systems, lab information systems, outpatient and inpatient systems, hospital information systems (HIS), radiology information systems (RIS), storage systems, picture archiving and communication systems (PACS), etc.) to manage clinical information such as, for example, patient medical histories, imaging data, test results, diagnosis information, management information, financial information, and/or scheduling information. These healthcare information systems are used to implement different types of workflows in which clinical information is generated, updated, augmented, and/or otherwise processed for one or more purposes.
A simple service that uses a cache to return data typically receives an identifier, checks to see if the identifier is in the cache and, if found, returns the data from the cache. If the identifier is not found in the cache, the service retrieves the data from another service, file system, or database. The service then stores the data in the cache and returns the data. The next time the data is needed, a call to another service is not necessary.
For this cache operation to work, each identifier must uniquely identify one item in the cache. If the data in the cache can be represented by more than one identifier, then the cache either needs to store the data multiple times under each identifier, or store all the identifiers for each data item.